Four leading members of Yemen's Al Qaeda branch have been killed in a suspected US drone strike in the east of the country, security officials and news outlets close to the Islamic State militant group said on Tuesday.The suspected US drone fired rockets in the southern port of Mukalla on Monday, killing the Al Qaeda leaders who were based in the city's presidential residence, according to security officials. The rocket attack targeted a car parked outside the presidential compound, officials said. The IS-affiliated Amaq News Agency said that the four slain Al Qaeda militants included Maamoun Hatem, who was believed to be an IS sympathiser. Last week, a video released by Al Qaeda in the Arabian Peninsula (AQAP) said its prominent member Nasser bin Ali al-Ansi, his son and several other fighters were killed after a US drone hit their convoy in Yemen's Hadramout governorate. Militants captured Mukalla last month from the Yemen army and seized the city's Riyan airport from one of Yemen's infantry units.